Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8a37ae36ff5b8c1…

MALICIOUS

PDF

85.8 KB Created: 2021-06-27 01:15:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 7c3060ad14853562441373b9b5446bf3 SHA-1: 36d38fde69e4b92fb741cd77950c02e7ad1e00a8 SHA-256: d8a37ae36ff5b8c1daf3e2f8e84137472947a15e8f7672733696999ff75275bf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress upload sites and other disposable hosting domains. The document body is heavily obfuscated and unreadable, suggesting it is not intended for direct user interaction but rather to facilitate the distribution of malicious content via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://copy2d.com/ftp/image/file/33595456807.pdf In PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609f66c340ba5---fedepopesajunisid.pdfIn PDF document text
    • http://industrialdevices.in/uploads/baxozujikuzawu.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/939f937c2880e5b9bc3583cb5f355b0b/tuzolibo.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609e86e71ba4b---74172582117.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160c09d3d5ce7a---naxegowud.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/3eeb288f40853ffb3e3be07404849bd2/teluridesikakelirenini.pdfIn PDF document text
    • http://wenxuezj.com/images/File/lovet.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160866bae98f9f---nulasori.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160bd5fe567637---2916062544.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c092ae46c54---61681360979.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/c2436f5b6b871ee3f92f802cf615c629/dubawagowigovirab.pdfIn PDF document text
    • http://dienmaythanglong.org/uploads/files/47483992791.pdfIn PDF document text
    • http://naturallabs.fr/userfiles/file/2503703403.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aca7748a26d---fozagapemenimozulevobot.pdfIn PDF document text
    • http://www.bash.cl/media/file/82261802282.pdfIn PDF document text
    • https://biovuspharma.net/userfiles/files/libovof.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/dajapopimo.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1609d4415d0d92---73367062887.pdfIn PDF document text
    • https://makiriaszto.hu/ckfinder/userfiles/files/55083157770.pdfIn PDF document text
    • https://yellowstonewildlife.com/5329536571.pdfIn PDF document text
    • http://kinel-hunter.ru/upfiles/file/juxar.pdfIn PDF document text
    • http://groupkaishan.com/d/files/nagovunixivowavuku.pdfIn PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ab77876e94a---9380907897.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/vchj39nv7v213hcromgctg91l1/moresizumetub.pdfIn PDF document text
    • http://coyada.com/up_images/up_images/fiwiragawigojirisas.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609948222610d---62008353433.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=croup+sounding+cough+only+at+nightPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001063c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1063C 16516 bytes
SHA-256: 1410cc93801f4b98384b0b55df0b6b243a561da3574a9f8d7936523d6e9ba988
font_02_sfnt_off000130bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130BB 10908 bytes
SHA-256: d270aac9aa066d19679b4ef7f83584044ba7722158277173f7481693fb03011c